1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to a data recording head and a method of manufacturing the same and, more particularly, to a perpendicular magnetic recording head and a method of manufacturing the perpendicular magnetic recording head.
2. Description of the Related Art
Methods of recording data in a magnetic recording medium can be classified into either horizontal magnetic recording methods or perpendicular magnetic recording methods depending on how data is recorded. In horizontal magnetic recording methods, data is recorded using a magnetic layer having a magnetic polarization, which is aligned parallel to the surface of the magnetic layer. In perpendicular magnetic recording methods, data is recorded using a magnetic layer having a magnetic polarization, which is aligned perpendicular to the surface of the magnetic layer. Aligning the magnetic polarization perpendicular to the surface of the magnetic layer allows perpendicular magnetic recording methods to achieve a greater recording density than horizontal magnetic recording methods.
A process by which data is written to a magnetic layer can be seen as an interaction between the magnetic layer and a magnetic head. Therefore, there is a need to improve both the magnetic head as well as the magnetic layer in order to record data at high density.
FIG. 1 is a cross-sectional view of a related perpendicular magnetic recording head.
Referring to FIG. 1, the related perpendicular magnetic recording head includes a main pole p1 and a return pole p2. An upper end of the main pole p1 contacts an upper end of the return pole p2, and lower ends of the main pole p1 and the return pole p2 are spaced a predetermined interval apart. A magnetic field required for recording data is generated between the lower ends of the main pole p1 and the return pole p2. A portion between the upper end and the lower end of the return pole p2 is curved. The curved portion of the return pole p2 is spaced from the main pole p1. A predetermined portion of the main pole p1, which corresponds to the curved portion of the return pole p2, has a coil c wound around it. The coil c does not contact the main pole p1 or the return pole p2. As current flows through the coil c, a magnetic field is generated, and this magnetic field is concentrated on the main pole p1. The return pole p2 constitutes a magnetic circuit together with the main pole p1. A dotted line B connecting the lower end of the main pole p1 to the lower end of the return pole p2 denotes a magnetic circuit formed during the recording of data.
In the related perpendicular magnetic recording head the main pole p1 is generally formed of a material having a large saturation magnetization and a high conductivity. A large eddy current can be generated in a material having a large saturation magnetization and a high conductivity. This eddy current increases the inductance of the coil c causing signal delay. Accordingly, when an eddy current is generated, there can be an increased time interval between when a write current is supplied to the coil c and when data is recorded to the magnetic layer.
FIG. 2 is a graph showing the signal delay that can occur in the related perpendicular magnetic recording head of FIG. 1. Referring to FIG. 2, first and second plots G1 and G2 show the variation of a recording magnetic field according to time when the specific resistance of the main pole P1 is 10 μΩ·cm and 100 μΩ·cm, respectively. A third plot G3 shows the variation of the write current according to time.
Referring to FIG. 2, it can be seen that an interval I1 between the first plot G1 and the third plot G3 is greater than an interval I2 between the second plot G2 and the third plot G3. This shows that the smaller the specific resistance of the main pole P1 (i.e. the greater the conductivity of the main pole P1), the larger the signal delay. Accordingly, it is difficult to realize a high density data recording apparatus with good write properties using the related perpendicular magnetic recording head. Additionally, the signal delay can be further increased during high-frequency operation, where the variation of the magnetic field according to time is great, making such recording operations irregular.
Illustrative, non-limiting embodiments of the present invention overcome the above disadvantages and other disadvantages not described above. However, the present invention is not required to overcome the disadvantages described above, and an illustrative, non-limiting embodiment of the present invention may not overcome any of the problems described above.